This disclosure relates to data transmission in communication systems and, more specifically, to reducing crest factors. In a communication system, a crest factor of a signal may represent a ratio of peak values to the effective value of the signal. In some cases, a crest factor may be calculated by dividing the peak amplitude of a signal by the root mean square of the signal. Therefore, the crest factor may indicate the peak-to-average power ratio of the signal. A signal with a high crest factor may distort the linearity of a power amplifier in a transmitter. Therefore, in some cases, a transmitter may reduce the crest factor of a signal before transmitting the signal.